While moving solids inside an object or an apparatus or inside a part of apparatus (for example, in a pipeline or similar with fluid for the sake of transportation, sizing or classifying), problems occur when for some reason the fluid moves forward but does not carry the solid material with. The motion of the solid material then slows down and finally stops. The solid material starts to accumulate and ends up with blocking the object.
For the above mentioned reason water should be added on the way continuously for process reasons or temporarily for improved material flow, to open a blockage or to add for example reagents into a process flow in a pipeline or in a process equipment.